It's deceptively simple, here is the process for the metalizer version.
1. Base application of Testors Aluminum Metalizer. When applying don't get too far away with your strokes as you don't want it dustier than it already is. If your not familiar with metalizer it lays down with a slight dusty finish.
2. Draw the pattern. Using micro brush, artists stump, or Tamiya q-tip draw your pattern on the finish. (This is the tricky part if you make a mistake its all over, you will need to re-spray the metalizer. The pressure of the drawing action will polish the turning mark into the finish.
3. "Dust" the surface. At this point you basically have a metallic version of "wash me" written on a very dusty car. The shiny squiggle pattern is "lower" than the dusty parts around it. The next step is to lightly dust the loose metallic particles off of the part. DO NOT POLISH. Dusting can be done with a large flat brush, again lightly.
4. Seal it up. If you intend to weather or wash the part you will need to seal it, I found acryilc or water based gloss coats work best. Stay away from metalizer sealer for this technique. Mine is shot with Alclad Aqua Clear.
This has some real potential, I can see even producing a "Spirit of St Louis" turned machined look with a punched pad attached to a tooth pick or the like.
ts a nerve racking ordeal, so practice on some parts before you commit.